Video: Are you being overcharged at the gas pump?

Closed captioning of: Are you being overcharged at the gas pump?

>>>back now at 7:43. and this morning on rossen reports, what consumers are calling a billion dollar rip-off that could be overcharging you at the
gas pump
. "today" national investigative correspondent
jeff rossen
is here with the story. jeff, good morning.

>>good morning. you don't need me to tell you
gas prices
are incredibly high right now and only getting worse. if you're anything like me you shop around for the best price. but consumer groups say, there is a summertime secret at
gas stations
. cheating you at the pump, out of billions of dollars. talk about sticker shock. $4. $4.50. more than $5 for gas. we're all feeling the squeeze.

>>gas prices
are getting crazy.

>>i'm spending way too much money for the gas.

>> reporter: but consumer watchtalks like judy duggen say many drivers don't even know the half of it.

>>it's a huge rip-off of american drivers.

>> reporter: you see, when it's hot outside and the gasoline is warm, consumer advocates say you're not getting what you pay for.

>>every time you stick that nozzle in your tank on a hot day, you're getting cheated.

>> reporter: here's the issue, when gas gets hot it loses energy. meaning your car gets fewer
miles per gallon
. fill up at 60 degrees and the typical car can go
500 miles
. but fill it up when it's
90 degrees
, you get ten miles less out of that same tank. but guess what, you're still paying the same amount at the pump.

>>there's no way that we can tell what kind of value you're getting when we pull in to the
gas station
.

>> reporter: in fact, according to the
2007
congressional report, persamericans were paying an estimated $1.5 billion extra for gas in just that one summer. and
gas prices
had skyrocketed since. is this fixable?

>>yes, there's technology on the market that would fix it.

>> reporter: gas pumps with special meters would give you the right amount of gas for your money, based on the heat. those pumps are available today. but the
gas stations
won't install them. in fact, they're fighting it.

>>we simply don't agree that the is worth the squeeze.

>> reporter: he says they're already giving consumers the best deal they can. that drivers benefit in
cold weather
and installing the new pumps would just be too expensive.

>>putting a $2.4 billion cost on
gas station
owners would only transfer $2.4 billion to the consumer.

>> reporter: so you're saying if they put this technology into place we have to pay for it?

>>of course.

>> reporter: but here in canada they've been doing it for nearly two decades. now 90% of
gas stations
use these pumps. that measure and adjust for temperature. so on a hot day, you actually get more gas for your money. consumer advocates say here, no matter what the weather, you actually get what you're paying for. now,
angry american
drivers have filed
class action
lawsuits against
gas station
chains in 21 states. calling it fraud. hoping to force
gas stations
to install the high test pumps. what is your message to the
oil industry
, to these
gas stations
?

>>now it looks like the big companies are taking action as part of a
legal settlement
, costco has agreed to install the new pumps at its
gas stations
in warm weather states, pending court approval. and now three of the
big oil
companies, bp, shell and
conoco phillips
, well they're settling, too. debt tails of that settlement still unclear. but this is not over yet. not by a long shot. other
gas station
chains are fighting the lawsuit. savannah, they'll be in court next month. we're going to
keep an eye
on this because i think a lot of consumers maybe want this change.

The pain at the gas pump is palpable. Making it worse: Consumer groups say a summertime gas station secret cheats drivers out of billions of dollars. And chains are fighting against changing the rules. TODAY National Investigative Correspondent Jeff Rossen reports.

"Every time you stick that nozzle in your tank on a hot day you're being cheated," Dugan told TODAY. "It's a huge rip-off of American drivers."

When gas gets hot, it loses energy. That means your car gets fewer miles per gallon. Fill it up at 60 degrees and the typical car can go 500 miles. But fill it up when it's 90 degrees and you get 10 miles less out of that same tank.

A solution exists: Gas pumps with special meters would give you the right amount of gas for your money based on the heat. But stations are fighting against implementing it.

"We simply don't agree that the juice is worth the squeeze," said Dan Gilligan, an official from the Petroleum Marketers Association of America. Gilligan said gas stations are already giving consumers the best deal they can, and drivers benefit in cold weather. Installing the new pumps would be too expensive, he said, and we'll wind up paying more anyway.

"Putting a $2.4 billion cost on gas station owners would only transfer $2.4 billion to the consumer," Gilligan said.

In Canada, they've been implementing the technology for nearly two decades. Ninety percent of gas stations use pumps that measure and adjust for temperature. When it's hot, they'll give you more gas for your dollar. Consumer advocates say you get what you pay for there, no matter the weather.

American drivers have filed class-action lawsuits against gas station chains in 21 states, calling the practice fraud and hoping to force gas stations to install the high-tech pumps.

As part of a legal settlement, Costco agreed to install the new pumps at its gas stations in warm weather states, pending court approval. And now, three of the big oil companies — BP, Shell and ConocoPhillips — are settling too, though the details of the deal are still unclear.

Other gas station chains continue to fight the lawsuits and will be in court next month.

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